Bridge and cement retainer for well bores



Nov. 7,'- 1939. R. cu BAKER BRIDGE AND' CEMENT 'RETANER FOR WLLBORESFiled Oct. l0, 1936 ,$47A fav BY v - ATTORNEY Fwf? Patented` Nov." 7,1939 PATENT OFFICE BRIDGE ,AND CEMENT RETAINER FOR WELL BORES Reuben C.Baker, Coalinga, Calif., assignor to Baker Oil Tools, Inc., HuntingtonPark, Calif., aeorporation of California Application october 1o, 193s,seria; No. icaoro 7 claims. (ci. 16s-12) This invention relates todevices for use during the drilling or reconditioning of oil well bores.

It is the principal object of the present invention to provide animproved bridge plug and .5 cement retainer which may be lowered into awell bore and then actuated by uid pressure to expand into intimatecontact and packing relation with the wall of the bore, both to form aseal between the device and the wall of the bore, and

to secure the device in position inthe bore.

' In practicing my invention, I provide a hollow body member which maybe detachably secured to the lower end of a string of running in tubingand run into place in a well bore.. The body member is tted with anormally collapsed packing member which, after the device is positionedin the bore, may be expanded by iiuid pressure into packing relationwith the wall of the bore and retained in such condition. The body isprovided with back pressure andbridging valve means to enable it to beused in various capacities.

` One form which the invention may assume is exemplied in the followingdescription and illustrated by way of example in the accompanyingdrawing, in which:

Fig. 1 is a view in central longitudinal section through a deviceembodying the preferred form of my invention with the parts thereof inthe position which they assume when the device is being lowered into awell bore.

Fig. 2 is a similar view with the exception that the packing element ofthe device is shownin expanded condition.

Referring more particularly to the accompanying drawing, I0 indicates anelongated cylindrical body member, the same being formed with a centrallongitudinal passageway II formed coaxially therethrough. At its lowerend this passageway -terminates in a valve vseat- I2 controlled by aspring-pressed back pressure valve I4 which opens downwardly. When thisvalve I4 is seated, it is obvious that the lower end of the passagewayII will be closed and uid will be unable to pass upwardly through vthebody, althoughl fluid under properv pressure may be forced downwardlythrough the body, opening the valve I4 and discharging.

`The valve I4 is tted with a valve stem I5 guided in a suitable bearingI 6 formed in the body. An expansion spring I1 is positioned between the-guide I6 and an enlarged head I8 secured on the upper end of the valvestem I5.

It will be noticed that the passageway II is the .numeral I9. Mountedwithin this reduced bore I9 is a trip sleeve 20 which is hollow andcylindrical, and which-is formed with a trip ball valve seat 2| at itsupper end. The trip sleeve 20 is formed with depending legs 22 which areAsecured to the valve stem head I8 by means of a shear pin 23. The tripsleeve 20 is secured in position within the reduced bore I9 by a shearpin 24. The positionof the sleeve so secured is such as to hold thevalve I4 unseated so that when the device is being run into the hole,uid may freely passv upwardly through the body, and likewisecirculatingor washing iiuid may be pumped downwardly through the body.

Arranged about the exterior periphery of the body I0 is an elongatedcylindrical packing member 25, preferably formed of rubber or some othersuitable pliable material. The lower end of this packing member 25 issuitably anchored to the lower end of the body by means of a clampingring 26 screwed to the body, as illustrated. The upper end of the packinmember 25 has a 'ring 21 secured thereto which.4 slidably mounted on theexterior of the body`.\ The ring 21 carries an interiorly arranged splitlatch ring 28 adapted to engage circular serrations 29'formed about theexterior of the body. These serrations permit the ring 21 and its latchring 28 to move longitudinally and downwardly of the body I0 but not inthe opposite direction.

Arranged on the body and slidable with respect thereto is a circularpiston 39 which is reciprocable in a circular cylinder 3| formed betweenthe exterior perimeter of the body I0 and' the interior perimeter of acylinder member 32 threadedly secured to the body as at 33. At its upperend the cylinder 3| communicates with the interior bore Il of the bodyl0 through ports 34. The lower end of the circular piston 30 abutsagainst the upper ring 2 1 ofthe packing member 25 so that whensuiiicient uid pressure is built up within the cylinder 3| to move thepiston 39 downwardly, it will move'the ring 21 downwardly and therebyexpand the packing member 25 aspacking member, the latter will retainthis condition due to the engagement of lthelatch ring passage of fluiddownwardly through the body.v

This is accomplished by dropping a trip ball 35 downwardly through therunning Vin tubing,

which ball is of a diameter that it will seatl on the seat 2| ofthe tripsleeve 20 and shut oil downward circulation. The shear pin 24 is ofsuiiicient strength to resist shearing until the pressure built upwithin the. body is sufcient to actuate the piston 30 and expand thepacking 5 member 25 las described. However, after the packing member hasbeen expanded into tight contact with the wall of the hole, the downwarduid pressure is increased to a point suiiicient to shear the pin 24 andthe pin 23 so that the trip ball 35 and the trip sleeve 20 will nolonger interrupt the iiow of fluid downwardly .through the body. Thisalso will release the valve I4 so that it may seat on the seat I2.

The running in'tubing indicated by the numeral 36 is threaded into theupper end of the body I0 with a left-hand thread so that after the bodyhas been secured in position in the well bore, the running in tubing maybe disconnected from the body and withdrawn.

At the junction between the reduced bore I 9 in the body and theuppermost portion of the larger bore is a' bridging valve seat 31adapted to receive a bridging ball valve 38 shown in dotted lines inFig. 2, which ball may be dropped downwardly into position at any time.This ball is positioned as indicated in Fig. 2 when it is desired thatthe device function as a bridge plug. That is to say, the valve I4 willprevent the upward flow of fluid through the device and the bridge valve38 will prevent the iiow of fluid downwardly through the device,consequently effectively bridging the bore,

In operation of the device, thedevice is constructed substantially asillustrated and described and is mounted on the lower end of the runningin tubing 36 and run into the hole. During the running in process, fluidmay freely pass upwardly through the device to enable-it 4to be lowered.Likewise, circulation can be established downwardly through the deviceat any time. After the device has been positioned at the proper pointalong the bore, the trip ball 35 is dropped through the running intubing and will seat on the seat 2l of the trip sleeve 20. By means ofthe pumps,

'45 sumcientuid pressure is then built up in the body I0 above the ball35 to force the piston 30 downwardly a suiiicient distance to tightlyexpand the packing member 25 into contactwith thewall ofthe hole. Due tothe fact that the w packing member 25 isformed of pliable material, itwill conform to the irregularities of the bore and therebyitightlygripthe wall of the hole as well as forming an effective seal between thebody I0 and the wall of the hole. It may be stated 5l that the length ofthe packing member 25 may be any length desired or necessary to effectthe result. Thereafter' the uid pressure is increased sufficiently toshear the pins 2 3v and 24 to enable the valve I4 to 'seat on its seatso that it lwill 00 .function as a back pressure valve. If it is sodesired, washingiluid or cement may be then pumped downwardly throughthe body into the bore below it, and the valve I4 will function toprohibit the back ilow of this material upwardly through the body.- Ifitis desired to bridge the well, the ball 38 is then dropped intoposition as described'to eiect the bridging operation.v 'I'he running intubing 36 is then unscrewed from the body III and removed from the hole.

70 If at any time it is desired to remove the device from the bore, itcan be readily drilled out due to the foot' that it is constructed ofmaterials that can be readily drilled out.

While I have shown the preferred form of my y -radially expand the same,and latch means for u' u invention, it is to be understoodA that variouschanges may be made in its construction by those skilled in the artwithout departing from the spirit ofthe invention as defined in theappended claims.

Having thus described my invention, what I 5 claim and desire to secureby Letters Patent is:

l. A device of the character described comprising a body adapted to bedetachably secured to the lower end of running in tubing, said bodyhaving a passageway formed coaxially there- 10 through, an elongatedsleeve-likev packing member of pliable material secured to the body atits lowermost end, and fluid pressure actuated means carried by the bodyadapted to move the upper end of said packing member toward its secured15 end to radially expand the same, and means for retaining said packingmember in its expanded position.

2. A device of the character described comprising a body adapted to bedetachably secured to t0 the lower end of running in tubing, said bodyhaving a passageway formed coaxially therethrough, anelongated-sleeve-like packing member of pliable material secured to thebody at its lowermost end, iiuid pressure actuated means 25 carried bythe body adapted to move the upper end of said packing member toward itssecured end to radially expand the same, and latch means for latchingsaid end that is moved in a set position, V

3. In aodevice of the character described, a v body adapted to beattached to the lower end o1 a string of running in tubing, asleeve-like packing member of pliable material arranged concentricallyabout said body and secured at its lower 35 end to said body, the upperend of said packing member being adapted to be moved downwardly towardthe secured end, and iluid pressurel actuated means carriedby the bodyto engage the upper end of `said packing member to move the 40 samedownwardly in response to fluid pressure built up in the body. 4. Adevice of the character described comprising an elongated cylindricalbody adapted to be attached to the lower end of a string of running intubing, said body having a longitudinal passageway formed therein, aback, pressure valve to control the ow of uid upwardly through the body,means adapted to be positioned in said passageway to prevent the passageof uid downwardly through the body when said iluid is below apredetermined pressure, a packing member of -pliable materialsurrounding' the body and capable of radial expansion when axiallyshortened, iluid pressure actuated means actuated by a pressure lessthan said predetermined pressure for axially shortening said packingmember to radially expand the same. I

5. A device of the character described comprising an elongatedcylindrical body adapted to be attached to the lower end of a string ofrunning in tubing, said body having a longitudinal passageway formedtherein, a back pressure valve to control the ilow of fluid upwardly.through the body, moans adopted to be positioned in said pas- 5 sagewayto prevent the passage of iluid downwardly through the body when saidiluid is below a predetermined pressure, 'a packing member. gf

pliable material surrounding the body and capable of radial expansionwhen axially shortened, iiuid pressure actuated means actuated by apressure less than said predetermined pressure for axially shorteningsaid packing-member to retaining said packing member in its shortenedcondition.

6. A device of the character described comprising an elongatedcylindrical body member havving a passageway formed longitudinallytherethrough ,and adapted to be attached to the lower end of a string ofrunning in tubing, means adapted to be positioned after said body ispositioned in a Well bore to obstruct the passage of iluid downwardlythrough the body, said means being renderedv in'eiective by a uidpressure built u lin the body exceeding a predetermined press e, anelongated packing sleeve carried by the body about its perimeter andsecured at one end to the body, -a cylindrical piston carried by thebody and engaging the other end of the packing member and actuated by auid pressure less than said predetermined pressure to move said ber andadaptei end of the packing member toward the fixed end thereofand-thereby radially expandsaid packing member, and latch means forlatching said moved end in position maintaining said packing memberexpanded.

7. In a device of the character described a body member adapted to bedetachably'secured to the lower end of a running in tubing, "anexpansible packing member surrounding the body member said packingmember being normally collapsed, uid responsive means carried by thebody memto engage the upper portion of the expansble.j packing memberwhereby said packing member will be expanded in response to fluidpressure and means Afor retaining said packing member in- 'its expandedposition,

' REUBEN C. BAKER.

